It might have been that once the Earth started to warm, some animals weren't able to adapt. Or possibly because new needs had to be met, so they found new animals to domesticate that could help with the new situation.
Grievances of king george
The fall of Constantinople
During World War I, Germany had been blockaded, so they didn't have the fertilizer for their crops and the food to survive, which then led to deaths. After the war, Germany was just really inefficient, and they had major problems. These problems then led to Hitler becoming the tyrant of Germany, which then led to World War II because he blamed all of the problems on the Jewish people, which then made even more problems.
